Hi, If you run the demo for persp (I have R 1.7), you will see that there is a good example of 'coluring' a volcano according to different heights, just try
> demo(persp) and check out the code. You probably will find it too complicated as I did, I was trying to do the same and honestly I wasn't able to. However, there is a way around and it is to use the function wireframe from the lattice package > library(lattice) > ?wireframe If you run through the help examples you'll see that it is a lot easier to colour the surfaces the way you want using this function. However, wireframe is extreMELY slow, so, if you have a big matrix it might be a pain in the behind. Also, the way you feed the data to wireframe is different to the way you do it with the persp function. I hope this is of any help. M. ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
